Molecular studies of BKCa channels in intracranial arteries: presence and localization.
Large conductance calcium-activated potassium channels (BK(ca)) are crucial for the regulation of cerebral vascular basal tone and might be involved in cerebral vasodilation relevant to migraine and stroke. We studied the differential gene expression of mRNA transcript levels and protein expression of the BK(Ca) channel in rat basilar, middle cerebral, and middle meningeal arteries by reverse transcription polymerase chain reaction (RT-PCR), quantitative real-time PCR, and Western blotting. Distribution patterns were investigated using in situ hybridization and immunofluorescence studies. RT-PCR and quantitative real-time PCR detected the expression of the BK(Ca) channel mRNA transcript in rat basilar, middle cerebral, and middle meningeal arteries, with the transcript being expressed more abundantly in rat basilar arteries than in middle cerebral and middle meningeal arteries. Western blotting detected the BK(Ca) channel protein in rat basilar and middle cerebral arteries. In situ hybridization and immunofluorescence studies confirmed that the BK(Ca) channel mRNA and protein expression was localized to smooth muscle cells in all three intracranial arteries. The data thus suggest the presence and localization of both mRNA and protein expression of the BK(Ca) channel in the smooth muscle cell layer in rat basilar, middle cerebral, and middle meningeal arteries.
Wulf
Helle
H
Department of Neurology & Danish Headache Centre, Glostrup Research Institute, Glostrup Hospital, Faculty of Health Sciences, University of Copenhagen, Nordre Ringvej 69, 2600, Glostrup, Denmark. helwul02@glo.regionh.dk
Hay-Schmidt
Anders
A
Poulsen
Asser Nyander
AN
Klaerke
Dan Arne
DA
Olesen
Jes
J
Jansen-Olesen
Inger
I
D000199:Actins / Q000378:metabolism; D000818:Animals; D001488:Basilar Artery / Q000166:cytology / Q000378:metabolism; D015153:Blotting, Western; D002536:Cerebral Arteries / Q000166:cytology / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D017403:In Situ Hybridization; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D008297:Male; D020768:Middle Cerebral Artery / Q000166:cytology / Q000378:metabolism; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D034443:RNA Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014981:Xenopus
D000199:Actins; C494842:Kcnma1 protein, rat; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D015221:Potassium Channels; D012333:RNA, Messenger